Let's calculate 6487 x 6840
6487 × 6840 = 6840 × (6487)
+ 6840 × 7 resulting in 47880
+ 6840 × 80 what gives us 547200
+ 6840 × 400 which equals 2736000
+ 6840 × 6000 that results in 41040000

= 44371080
